I remember a set of audio tapes I listened to a while back done by a priest-friend of mine on this topic.

It's my understand that No, he cannot read our minds. He can act on outward expressions and on what we say, but he can't read our minds.

If we give permission, our guardian angels can read our minds.

You said:

Can Christians be possessed by a demon?

Sure! Although many times, what appears to be demon possession, is really someone with a severe mental condition. This is why the Church goes very cautiously in determining whether someone needs an exorcism.

Mike

Richard replied:

Hi Roy,

For what it's worth, I can give a little information. One point of Catholic doctrine about the angels and demons is that they cannot see people's thoughts: only God can read the soul. From this it follows logically that angels and demons cannot control anyone's thoughts. Of course they can see our visible actions.